Squeeze riveter



June 13, 1944.n F. A KAMAN 2,351,049y

SQUEEZE RIVETER Filed Deo. 26, 1941 2 Sheets-Sheet l IIL" will;

iL-l1 BY ATTORNEY.

June 13, 1944. F A KAMAN SQUEEZE RIVETER Filed Dec. 26, 1 941 2 Sheets-Sheet 2 mil! *will5 A TTORNEY.

Patented June 13, 1944 UNITED sapienza nlvimm Frank A. Kamari, Aurora, lll., assigner to Independent Pneumatlc Tool Company, Chicago, lll., a corporation of Delaware Application December 2s, 1941, serial No. taluni (Cl. 'za-4s) 8 Claiim.

This invention relates to portable power oper- -ated riveting tools of the compression or squeeze riveter type for cold riveting operations as coin monly employed in the airplane industry for driving aluminum and like rivets'.

` The principal object and purpose of my invention is to provide a riveting tool in which the riveting action automatically adjusts itself for rivets of dinerent lengths. This does away with the maintenance of an exact distance between the end of the riveting plunger and yoke elements of the tool for a definite diameter and length of rivet. In other words, where the machines as heretofore employed must be converted to the particular length of the rivet by the ma. nipulation of the plunger, yokes or rivet sets and then canbe -used only for that particular length of rivet 'without further manipulation, the riveter 'of my invention can drive rivets which vary in length within its range without any adjustmoved as a unit with the plunger by the power operated means of the tool until the plunger enments. This isa special advantage on production lines where simple and speedy methods are.

paramount in that the operator need only applyl the machine to the rivet and set the machine Y 'anywhere within the range of the total stroke.

The plunger, during the course of its travel, has

"no power until it encounters a resistance on contact with the work, whereupon, the power stroke comes into action and builds up the presi sure needed to drive a proper head on the rivetl andsecurely clamp the plates being riveted together. In short, in accordance with my invention, the plunger has a floating -power stroke which is inactive until called. upon, and then occurs as soon as the plunger meets a 'resistance on contact with the work regardless of the length of the rivet.

The riveter of my invention, once set up for Y. its range of jobs, needs no more interchanglng It requires no further of yokes and p lungers. tampering or adjusting for length variation of rivets. It obliterates the tedious problem of adjusting the riveter to its work and always supplies acorrect power stroke.

. In carrying out the objects of my invention, I provide a riveter in which the heavy pressure creating means for increasing the pressureo'nr the plunger when in contact with the work-is 55 closurewhead I3 and the piston inder 5 and provides a hand hold counters the work, whereupon, the resistance offered to the plunger will automatically bring the heavy pressure creating means into action to project the plunger on its riveting stroke with the lincreased pressure requiredfor a cold riveting operation regardless of the length of the rivet.

It is within the contemplation 'of my inventionl to accomplish the objects aforesaid by the use of a follower wedge which follows along with 'the plunger as it is moved up to the work and acts as a stop to set the heavy pressure creating means into action as soon as the plunger encounters la resistance on contact with the work.

Other and further objects of my invention will appear in the following specification taken in conjunction with the accompanying drawings in which- Fig..1is a longitudinal sectional view with parts in elevation of a portable power operated riveting tool constructed inaccordance with my invention;

Fig. 2 is a similar sectional viewtaken on line 2--2 of Fig. 1; 4

Fig. 2A' is a sectional view showing the valve in one position of its movement;

Fig. 3 is a cross-sectional view with parts in elevation taken on line 3-3 of Fig. 1;

Fig. 4 is a fragmentary longitudinal sectional view with parts in elevation taken on line 4 4 ofFigCl;

' Fig. 5 is a view showing the action of the fol- The machine illustrated comprises a housing I a frame 2 carrying a yoke 3 at the Bolts I connect the yoke to the frame as shown in Figs. 1 and 2. A main power cylinder 5 containing a piston 6 on a piston rod 'I is at thefendof the housing I o pposite the yoke 3. An end wall 8 of the housing I closes the front end of the cylinder 5, the rear end of said cylinder being yclosed by a wall member 9 secured to the cylinder 5 by screws I0 as `shown.

An auxiliary cylinder I I containing a piston I2 extends rearwardly from the end wall 9 in coaxial alinement with the main cylinder 5. \The cylinder II is smaller in diameter than the cylfor the tool.

The cylinder Il is closed at its rear end by a.

I2 in the cylmounting front end of 'the tool.-

inder Il is fixed to. an extension I4 or the piston rod 1 in the main cylinder 5. This provides for A inder II on the rear side of the piston I2 for supplying pressure fluid thereto. A port I8 connects the front end of the passage I with the cylinder 5 on the rear side of its piston- 6 when the latter starts on its forward or power stroke. By this arrangement pressure uid supplied to the main cylinder 5 will enter the auxiliary cylinder II and act simultaneously on the pistons of both cylinders to drive the pistons forwardly in unison. 'Ihe flow of pressure iiuid to and from the cylinders 5 and II is controlled by a manually operable throttle valve I1 mounted in the wall section 9 between the cylinders as shown inFigs. 2 and 2A. y

The valve I1 in the embodiment shown is slidably mounted in the head section 9 and is moved endwise in one direction by an actuating lever I3 pivoted at 4I!! on the head. section 9 and extending along the' auxiliary cylinder I I to be grasped therewith when holding the tool. The valve I1 is moved in the opposite direction by a spring (not shown) included in the valve assembly. 'I'he spring lowers the valve I1 to connect the front end of the auxiliary cylinder with the live air supply, while the lever I8 raises the valve to connect the rear end of the .power cylinder 5 with said air supply. For this purpose, the forward end of the lever I 8 is pivoted to the upper end of the valve member I1 as indicated generally in Fig. 1. The control valve I1 follows the construction and operation of the corresponding valve shown and described in the co-pending application of F. P. Forsaserial No. 306,254 filed Novembery 27, 1939, and owned by the. assignee of the instant application.

As shown in Figs. 2 and 2A, the valve I1 is provided with an inlet port 2I which-connects with an inlet opening 22 in the head section 9 and to which opening the compressed air supply hose (not shown) for the tool is attached. When the valve I 1 is raised to the position shown in Fig. 2, its port 23 connects the inlet port 2| to the rear end of the cylinder 5 through a pas sage 24 in the head section 9. At thesame time the front end of the cylinder I I exhausts through ports 25 and 26 in the valve and passages 21 and 23 inthe head section 9. It is to be understood that these ports are separated from the first on'es in a manner to function as herein described.

When the valve member I1 is lowered to the position-shown in Fig. 2A, the port 2| connects the inlet opening 22 with the rear end of the cylinder II through the port 25 and the passage 21. The cylinder 5 at this time exhausts through ports 23 andv 26 and passages 24 and 28. The latter is the exhaust passage for the valve in both positions. With the arrangement as described, depressing the lever I8 drives the pistons forwardly, while releasing the lever returns the pistons to the beginning of their power strokes.

Slidably mounted in the frame 2 at the front end of the tool is a riveting plunger or ram 29 in opposition to an anvil 38 on the yoke 3 as shown' herein. The plunger 29 extends into the housing I between the side walls 3|, 3I of the frame 2 and there carries a roller 32 which by a coiled spring 33 about the plunger is pressed into contact with the periphery of a co-operating cam element to be presently described.

'I'he mechanism embodying this cam element stroke.

'the lever 34 towards the plunger 29.

is located within the housing I between the side walls 3| of the frame 2 and is in part supported thereby as shown in Figs. 1 to 6. Said'mechanism comprises a lever 34 and a link 35, both located between the side walls of the frame 2 and .pivotally interconnected at their adjacent ends by a cross-pin 36. The opposite or upper end of the lever 34 is pivotally connected to the frame 2 by a fulcrum pin 31 which extends between and has its ends mounted in the side walls 3l of the frame. The ends of the pin 31 extend laterally beyond the frame and take into openings provided in the side walls 38, 38 of the housing I to hold the frame 2 within the housing when the parts are assembled as shown in the drawings. An additional cross-pin 39 is employed to hold the frame 2 within the housing I.

The lever 34 and the link 35 are each of the bifurcated, one-piece type, the link 35 fitting between the arm portions 40 of the lever. The latter at its fulcrumed end is provided with an integral web portion 4I extending rearwardly from the fulcrum 31 and provided on its upper side at its outer end with a rounded lug projection 42 for engagement with the inclined under surface 43 of a movable follower wedge 44 to be presently described. It is to be understood that the lever 34 and the link 35 .are located in the space between the forward end of the piston rod 1 and the rear end of the plunger 29 and serve to transmit the power of the rod 1 to the plunger 29 and also operate the cam to build up the pressure on the plunger on its riveting or power The rod 1 and the plunger 29 are arranged in parallelism with therod 1 ofi'set laterally to one side of the longitudinal axis of the plunger 29. l With this arrangement the link 35 occupies the diagonal position shown in Fig. 1 at the beginning of the power stroke of the tool.

'I'he rear end of the link 35 is .pivotally connected to the forward end of therod 1 through a connector 45 and a cross-pin 46. The side arms 41, 41 of the link 35 straddle the connector 45 and have elongated slots 48 to receive 'the opposite ends of the pin 46. The slots 48 provide for the swinging of the linkl 35 about its pivot pin 36 in the operation of the cam by the power of the tool. One or more c'oiled springs 49 are employed to normally swing the lower end of Two of these springs 49 are disclosed in the embodiment herein, one at each side arm 40 of the lever 34 and connected at their upper` ends thereto on to the rear of the fulcrum 31 and at their lower ends to the side walls 3| of the frame 2 below the line of movement of the connector 45. The side arms 40 of the lever 34 are provided below the web 4I- with rearwardly extending lug portions 50, 50 to provide anchorages for the uprperendsA of the springs 49 as shown.

The link 35 is provided on its hub section about the pin 36 with an integral cam portion 5I having a`curved cam surface 52 in eccentric relation to the pin 36. The cam surface 52 is on a gradually increasing curvature and is in constant contact withthe roller 32 on the plunger 29 as shown in Fig.,2. The cam portion 5I acts to project the plunger forwardly on its riveting strokeA atv an increased pressure when operated by the pistons s and lz.

The follower wedge 44 which controls the action of the cam 5I is located .within the frame 2 between its side walls 3I to the rear of the lever 34 and above the piston rod 1. A rod53 mounts the follower wedge 44 in the frame 2 for movement in parallel with the .rod 1 and the plunger 29. A recess 54 in the member 4,4 receives a coil spring 55 about the rod 53 for normally urging the follower wedge 44 towards the lever 34. The front end of the spring 55 seats against the bottom of the recess 54, while the rear end of the spring seats against a lug 55 formed integral with the top wall 51 of the frame 2 and in the path of movement of the wedge member 44.. The rod 53 is anchored in the lug 55 and has its opposite end supported in a drilled hole in the front body portion 58 of the frame 2 above the fulcrum pin 31 as shown in Fig. 1. The wedge member 44 fits against the top wall 51 of the frame 2, the co-acting surfaces 59 and 60 of these parts being flat and parallel to the `line of movement of the piston rod 1 and the plunger 29. The side walls 3| of the frame 2 may be cut out as at 6l to provide openings to reduce the weight of the frame and also facilitate reaching the parts therein when assembling and disassembling the tool. As indicated in the drawings, the frame 2 is insertable into the housing I through an opening at the front end of its side walls, 38. The front end of the frame 2 closes this opening when the frame is in place as shown in Fig. 1 Similarly, the top wall 51 of the frame 2 closes the upper part of the housing l when the parts are assembled as shown in Fig. 3.

The piston rod 1 and the follower wedge 44 have coacting abutments 62, 53. The abutment E2 extends upwardly from the connector 45 and lies in the path of movement of the abutment 63. The latter is carried by the follower wedge 44 as a tail piece and extends downwardly therefrom as shown. 'I'he follower wedge 44 is at the lug 56 at the rear end of the frame 2 at the start of the forward stroke of the pistons and the abutment 53 on the wedge member 44 lies on the rear side of the abutment 62 on the connector 45 as shown in Fig. 1. The purpose of the construction will presently appear.

The operation 'of the machine shown and described is as follows: The piston B is brought to the beginning of its power stroke by admitting 4I.

pressure fluid to thev front end of the auxiliary cylinder Il. This brings the pistons and I2' to the rear ends of their respective cylinders. The rod 1 in this rearward movement of the Distons moves the lever 34 and its connected link 35 l.

to the positions shown in Fig. l. At the same time the rod 1 moves the follower wedge 44 to its rearmost position due to the action ofthe abutment 62 on the abutment 63. The tool is now applied over the rivet to be set with the head Il,

of the rivet against the anvil of the yoke 3 and the shank of the rivet opposed to and in line with the plunger 29 as is well understood in this art. The plunger 29 is out of contactwith the shank end of the rivet because the clearance .u

space between the anvil and the plunger is suilicient to accommodate the longest rivet within the range for which the machine is designed.

- Power is now applied to move the pistons forwardly and the first action is to move the link and lever 34, and the plunger 29 forwardly as a unit until the plunger encounters the work, that is, the shank end of the rivet. This movement takes place rapidly as there is no resistance to hinder the unitary movement of the parts. During this movement the lower end of the lever 34 is moved forwardly and the wedge member 44 follows along to take up'the enlarging space between the lug projection 42 at the upper end of the lever and the opposed wall sur- 'within the range 4of the total stroke.

-face of the frame 2. As soon 'as the plunger curely clamp them together. The riveting pressure is increased due to the eccentric shape of the cam and proper setting of the rivet is obtained at the end of the plunger stroke: At the terminationof the riveting stroke the power is reversed and the parts are returned to their starting positions.

Due to the follower-,wedge 44 it is apparent that the riveting machine of myA invention will automatically set itself 'without manual adjustment of any kind to rivets of variouslengths within the range provided for the machine. wedge in following along with the lever 34 automatically` sets the pressure increasing means for action as soon as the plunger 29 encounters a resistance on contact with `the work and this occurs regardless of the length of the rivet. In all cases, as hereinbefore pointed out, the plunger during the course. of its travel has no power until it encounters some resistance, and upon meeting a resistance, its power stroke comes into action and builds up the necessary riveting pressure. It is this action which produces the floating power stroke which is inactive until called A lmachine canA drive rivets with a Variation in length of The machine has a power stroke of 515", but this power stroke can work anywhere The plunger 29 during the course of its travel has no power until it encounters the rivet and upon encountering this resistance the power stroke comes into action and builds up the pressure as above described. The dimensions given are by way of illustration and not by way of limitation.

The riveter may Ibe equipped Iwith a safety or pop-off valve (not shown) to guard against applying excessive crushing pressure to small diameter rivets. This valve is adjustable so that its blow-off pressure can be regulated. My invention asvherein disclosed is also applicable to riveters of a single -cylinder type, that is, which do not employ an auxiliary cylinder to return the pistons to the start of their power strokes. l

valve are so constructed and arranged that the power piston is moved in opposite directions by pressure uid supplied alternately to the opposite sides thereof. It is to be also understood, that any desired type of control v'alve means may be employed with my invention for supplying the pressure to and exhausting it from the power applying means of the tool.

If desired the side walls 3| 'of the frame 2 may be provided withv slots.64, 64 to guide the ends of the pin which mounts the roller 32 at the inner end of the plunger 29 as shown in Fig. 4. To facilitate ease of operation'roller or equivalent anti-friction bearings may be employed at the pivotal connection between the lever 34 and The the link 35 about the pin 36 and also at the pin 85 for the roller 32.

The details of construction and arrangement of parts shown and described may be variously changed and modified without departing from the spirit and scope f my invention, except as pointed out in the annexed claims.

I claim as my invention: Y 1. In a riveting machine for setting rivets of different lengths, a support, an anvil carried thereby, a riveting plunger slidably mounted on said support, a member movably mounted on the plying means carried by said member and operableA on said plunger, power actuated means on support rearwardly of the plunger, power multithe support for moving said member and said 4 plunger 'as a unit until the plunger grips the rivet between itself and the anvil and thereafter.

operating said power multiplying means to increase the pressure of the plunger on the rivet to upset the same, and power biased stop means movably mounted on the support independently f and following along with the member as the plunger is engaged with the rivet to hold the member against reverse movement upon the op- `eration of the power multiplying means on the plunger to upset the rivet to compensate for rivetsof different lengths.

2. In a riveting machine for setting rivets of diierent lengths, a support, an anvil carried thereby, a riveting plunger slidably mounted on said support, a lever pivoted at one end on the support, a link pivoted to the other end of the lever, cam means carried by the link in eccentric relation to its pivotal connection with the lever and operable on the plunger, power actuated means on the support connected with the link` Aand the support and following along with the lever as the plunger is engaged with the rivet to hold the lever against reverse movement upon the operationV of the cam means on the plunger to upset the rivet to compensate for rivets of diilerent lengths.

3. In a riveting machine for setting rivets of different lengths, a support, an anvil carried thereby, a riveting plunger slidably `mounted on said support, a lever pivoted at one end on the support and having a rigid projection in spaced relation to the support, power multiplying means carried by the lever at its other end and operable on the plunger. power actuated means on the support for moving the lever and the plunger as a unit until the plunger grips the rivet between itself and the anvil and thereafter operating the power multiplying means to increase the pressure ofthe plunger on the rivet to upset the same, and a spring biased wedge member movably mounted on the support and following along with the lever to'take up the space between the projection and the support as the plunger is en- :raged with the rivet to hold the lever against reverse movement upon the operation. of the power m'ultlplying'means on the plunger to upset the rivet to compensate for rivets of different lengths.

4. ln a riveting machine for setting rivets of different lengths, a support, an anvil carried thereby, a riveting plunger slidably mounted on the support and having a rigid projection in spaced relation to the support, power multiplying means carried by the lever at its other end and operable on the plunger, power actuated j means on the support for moving the lever and the plunger as a unit until the plunger grips the rivet between itself and the anvil and thereafter operating said power multiplying means to increase the pressure of the plunger on the rivet to upset the same, and a spring biased wedge member movably mounted on the support and following along with the lever to take up the space between the projection and the support as 'the plunger is engaged with the rivet to hold the lever against reverse movement upon the operation of the power multiplying means on the plunger to upset \the rivet to compensate for rivets of diierent lengths, saidwedge member having operative guiding and inclined surfaces between and in contact with the support and means onjthe support for moving the lever and A the plunger as a unit until the plunger grips Athe rivet between itself and the anvil and there-I after operating said power multiplying means to increase the pressure of the plunger on the rivet to upset the same, a spring biased wedge membermovably mounted on the support and following along with the lever to take up the space between the projection and the support as the plunger is engaged with the rivet to hold the lever against reverse movement upon operation of the power multiplying, means on the plunger to upset the rivet to compensate for rivets of different'r lengths, and guide means on the support to support the wedge member and the spring therefor.

6. In a riveting machine for setting rivets of .different lengths, a support, an anvil carried thereby, a riveting plunger slidably mounted on said support, a lever fulcrumed at one end on the support, power multiplying means carried by the lever at its other end and operable on the plunger, a power actuated element on the support for moving the lever and the plunger as-a unit until the plunger grips the rivet between itself and the anvil and thereafter operating said power multiplying means to increase the pressure of the plunger on the rivet to upset the same, a movably mounted spring biased wedge member on the support interacting with the lever and the support as the plunger is engaged with the rivet to hold the lever against reverse movement upon the operation of the power multiplying means on the plungerto upset the rivet to compensate for rivets of different lengths, and` coacting means on the wedge member and the element to return the wedge member to its starting position on the return movement of the element.

7. -In a riveting machine for setting rivets of different lengths, a support, an anvil carried thereby, a riveting plunger slidably mounted on relation to its pivotal connection with the lever and operable on the plunger, power actuated means on the support having a lost motion connection with the link for moving the lever and the plunger as a unit until the plunger grips the rivet between itself and the anvil and thereafter rotating the link to bring the cam means into action on the plunger to increase the pressure thereof on the rivet to upset the same, a' movably mounted wedge member on the support interacting with the support and the lever and following along with the lever as the plunger is engaged with the rivet to hold the lever against reverse movement upon the operation of the cam means on the plunger to upset the rivet to compensate for rivets of different lengths and spring means, one for urging the wedge member to'- wards the lever, and the other for holding the plunger against the cam means.

8. In a riveting machine for setting rivets of different lengths, a support, an anvil carried thereby, a riveting plunger slidably mounted on said support, a lever pivoted at one end on the support, a link pivoted to the other end of the lever, cam means carried by the link in eccen tric relation to its pivotal connection with the lever and operable on the plunger, a power actuated rod movably mounted on the support and connected with thelink for moving the same y and the lever as a unit until the plunger grips the rivet between itself and the anvil and thereafter rotating the link to bring the cam means into action on the plunger to increase the pressure thereof on the rivet to upset the same, a movably mounted spring biased wedge member on the support interacting with the lever and the K support and following along with the lever as the plunger is engaged with the rivet to hold the lever against reverse movement upon the operation of the cam means on the plunger to upset the rivet to compensate for rivets of different lengths, said wedge member being offset from the rod, and cooperating projections on the wedge member and the rod extending into the path of each other for returning the wedge member to its starting position on the return movement of the rod and permitting the wedge member to move with the rod on its power stroke towards the plunger.

FRANK A. KAMAN. 

